Merge pull request #1 from google/master

catch up

1 files changed, 93 insertions, 0 deletions

diff --git a/images/Makefile b/images/Makefile
new file mode 100644
index 000000000..1485607bd
--- /dev/null
+++ b/images/Makefile
@@ -0,0 +1,93 @@
+#!/usr/bin/make -f
+
+# Copyright 2018 The gVisor Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# ARCH is the architecture used for the build. This may be overriden at the
+# command line in order to perform a cross-build (in a limited capacity).
+ARCH := $(shell uname -m)
+
+# Note that the image prefixes used here must match the image mangling in
+# runsc/testutil.MangleImage. Names are mangled in this way to ensure that all
+# tests are using locally-defined images (that are consistent and idempotent).
+REMOTE_IMAGE_PREFIX ?= gcr.io/gvisor-presubmit
+LOCAL_IMAGE_PREFIX ?= gvisor.dev/images
+ALL_IMAGES := $(subst /,_,$(subst ./,,$(shell find . -name Dockerfile -exec dirname {} \;)))
+ifneq ($(ARCH),$(shell uname -m))
+DOCKER_PLATFORM_ARGS := --platform=$(ARCH)
+else
+DOCKER_PLATFORM_ARGS :=
+endif
+
+list-all-images:
+	@for image in $(ALL_IMAGES); do echo $${image}; done
+.PHONY: list-build-images
+
+%-all-images:
+	@$(MAKE) $(patsubst %,$*-%,$(ALL_IMAGES))
+
+# tag is a function that returns the tag name, given an image.
+#
+# The tag constructed is used to memoize the image generated (see README.md).
+# This scheme is used to enable aggressive caching in a central repository, but
+# ensuring that images will always be sourced using the local files if there
+# are changes.
+path = $(subst _,/,$(1))
+tag = $(shell find $(call path,$(1)) -type f -print | sort | xargs -n 1 sha256sum | sha256sum - | cut -c 1-16)
+remote_image = $(REMOTE_IMAGE_PREFIX)/$(subst _,/,$(1))_$(ARCH):$(call tag,$(1))
+local_image = $(LOCAL_IMAGE_PREFIX)/$(subst _,/,$(1))
+
+# rebuild builds the image locally. Only the "remote" tag will be applied. Note
+# we need to explicitly repull the base layer in order to ensure that the
+# architecture is correct. Note that we use the term "rebuild" here to avoid
+# conflicting with the bazel "build" terminology, which is used elsewhere.
+rebuild-%: register-cross
+	FROM=$(shell grep FROM $(call path,$*)/Dockerfile | cut -d' ' -f2-) && \
+		docker pull $(DOCKER_PLATFORM_ARGS) $$FROM
+	T=$$(mktemp -d) && cp -a $(call path,$*)/* $$T && \
+		docker build $(DOCKER_PLATFORM_ARGS) -t $(call remote_image,$*) $$T && \
+		rm -rf $$T
+
+# pull will check the "remote" image and pull if necessary. If the remote image
+# must be pulled, then it will tag with the latest local target. Note that pull
+# may fail if the remote image is not available.
+pull-%:
+	docker pull $(DOCKER_PLATFORM_ARGS) $(call remote_image,$*)
+
+# load will either pull the "remote" or build it locally. This is the preferred
+# entrypoint, as it should never file. The local tag should always be set after
+# this returns (either by the pull or the build).
+load-%:
+	docker inspect $(call remote_image,$*) >/dev/null 2>&1 || $(MAKE) pull-$* || $(MAKE) rebuild-$*
+	docker tag $(call remote_image,$*) $(call local_image,$*)
+
+# push pushes the remote image, after either pulling (to validate that the tag
+# already exists) or building manually.
+push-%: load-%
+	docker push $(call remote_image,$*)
+
+# register-cross registers the necessary qemu binaries for cross-compilation.
+# This may be used by any target that may execute containers that are not the
+# native format.
+register-cross:
+ifneq ($(ARCH),$(shell uname -m))
+ifeq (,$(wildcard /proc/sys/fs/binfmt_misc/qemu-*))
+	docker run --rm --privileged multiarch/qemu-user-static --reset --persistent yes
+else
+	@true # Already registered.
+endif
+else
+	@true # No cross required.
+endif
+.PHONY: register-cross